AC pressure switch R12/134a ?

Gmc s are all r12 s
Especially the 73 s

Jump the press sw, and gopherit

> Just remember on some modern R134 systems there is a low pressure switch
> that disables the compressor. This switch is set far too high for duracool
> to be effective.
>
>
>
> I know this happens on a 2003 for focus, and I suspect it happens on
> others.
>
>
>
> So my model is to use 134 on 134 systems and Duracool on R12 and maybe
> some older r134 systems
>
>
>
> ________________________________
>
> From: Gmclist on behalf of gene Fisher <
> mr.erfisher>
>
> Sent: Tuesday, December 13, 2016 1:26:46 PM
>
> To: gmclist
>
> Subject: Re: [GMCnet] AC pressure switch R12/134a ?
>
>
>
> The good news is
>
>
>
> Duracool works with what ever you have
>
> Just add 2 cans and see what happens
>
>
>
> No changes
>
> No replacement
>
>
>
> Just add 2 cans
>
>
>
>
>
>
>

>
>
>
> > I was kinda late in this Dura Cool stuff, as I had a false pre-conceived
>
> >
>
> > notion that R-12 was better than Dura-cool. As I was trained at GM TECH
>
> >
>
> > CENTER on auto AC. Old habits die hard but I retrofitted my own coach
> with
>
> >
>
> > Dura-cool to see for myself. Was I suprised to see a 40° drop between
>
> >
>
> > ambient outside air and duct outlet temps? Yes, I was. And at a whole
> bunch
>
> >
>
> > less pressure. Short fill a system like the GMC with R 134 or R 12, and
> you
>
> >
>
> > get very poor performance. With Dura-cool, short filling is the secret to
>
> >
>
> > maximum cooling. Two cans, plus a bit more in most coaches is all that is
>
> >
>
> > needed. Stuff is cheap, molecules are bigger, so less prone to leaks. It
> is
>
> >
>
> > what I recommend.
>
> >
>
> > Jim Hupy
>
> >
>
> >
>
> >
>

>
> >
>
> >
>
> >
>

>
> >
>
> > > > R-134, Duracool, antifreeze, oil, gasoline, and propane that are in
>
> > your
>
> >
>
> > > coach are all flammable.
>
> >
>
> > >
>
> >
>
> > >
>
> >
>
> > > We already have what, 17 gallons of propane on board in the motorhome?
>
> >
>
> > > What's another few ounces...
>
> >
>
> > >
>
> >
>
> > > I agree with what is said above... 134a should stain in 134a based
>
> >
>
> > > systems. Keep R12 systems charged with R12 or some form of HC. Too
> many
>
> >
>
> > > drawbacks to converting to 134a, but the most important drawback is the
>
> >
>
> > > reduction in efficiency. If 134a improved cooling over R12, all those
>
> > other
>
> >
>
> > > drawbacks would be worth it, IMO... But to spend all that effort and
> $$
>
> >
>
> > > to convert an already taxed system to something that works worse?
>
> >
>
> > >
>
> >
>
> > > --
>
> >
>
> > > Mark S. '73 Painted Desert,
>
> >
>
> > > Manny 1 Ton Front End,
>
> >
>
> > > Howell Injection,
>
> >
>
> > > Leigh Harrison 4bag and Rear Brakes,
>
> >
>
> > > Fort Worth, TX
>
> >
>
> > >
>
> >
>
> > > _______________________________________________
>
> >
>
> > > GMCnet mailing list
>
> >
>
> > > Unsubscribe or Change List Options:
>
> >
>
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>
> >
>
> > >
>
> >
>
> > _______________________________________________
>
> >
>
> > GMCnet mailing list
>
> >
>
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> >
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> >
>
> >
>
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>
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>
 
I have a large tank (30 pound?) of R-134 here. I use it in R-134 vehicles and appliances. I also have a stock of Duracool. It goes in all R-12
applications.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> I have a large tank (30 pound?) of R-134 here. I use it in R-134 vehicles and appliances. I also have a stock of Duracool. It goes in all R-12
> applications.

+1 on the 30 pounder... Sam's Club usually has a great price on the 30s. Think it ended up costing 1/3 what you pay for the smaller cans when I
bought one 5 years ago... And I believe I paid $200 for a 30 pounder of R12 like 15 years ago... Paid about the same for an R22 30 as well 5 years
ago. So far, the price of refridgerant only goes up as it is discontinued... R12 is going for somewhere between $700 and $1000 for a full 30 pounder
now. R22s starting to go up too, and I assume 134a will once they stop making it...

Use it as long as you need it... Then sell it when you no longer have any ACs that use it. Not a bad ROI...

Speaking of which, I've never used any sort of HC12 in an AC, but I do understand the benefits of doing so over charging with 134a or even R12...
However, what is the benefit of using a product like Duracool, vs just charging with straight propane?

--
Mark S. '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX
 
So
Why does the rest of the world use a blend like duracool?

>
> > I have a large tank (30 pound?) of R-134 here. I use it in R-134
> vehicles and appliances. I also have a stock of Duracool. It goes in all
> R-12
>
> > applications.
>
>
>
>
>
> +1 on the 30 pounder... Sam's Club usually has a great price on the 30s.
> Think it ended up costing 1/3 what you pay for the smaller cans when I
>
> bought one 5 years ago... And I believe I paid $200 for a 30 pounder of
> R12 like 15 years ago... Paid about the same for an R22 30 as well 5 years
>
> ago. So far, the price of refridgerant only goes up as it is
> discontinued... R12 is going for somewhere between $700 and $1000 for a
> full 30 pounder
>
> now. R22s starting to go up too, and I assume 134a will once they stop
> making it...
>
>
>
> Use it as long as you need it... Then sell it when you no longer have any
> ACs that use it. Not a bad ROI...
>
>
>
> Speaking of which, I've never used any sort of HC12 in an AC, but I do
> understand the benefits of doing so over charging with 134a or even R12...
>
> However, what is the benefit of using a product like Duracool, vs just
> charging with straight propane?
>
>
>
> --
>
> Mark S. '73 Painted Desert,
>
> Manny 1 Ton Front End,
>
> Howell Injection,
>
> Leigh Harrison 4bag and Rear Brakes,
>
> Fort Worth, TX
>
>
>
> _______________________________________________
>
> GMCnet mailing list
>
> Unsubscribe or Change List Options:
>
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
 
>
> Speaking of which, I've never used any sort of HC12 in an AC, but I do understand the benefits of doing so over charging with 134a or even R12...
> However, what is the benefit of using a product like Duracool, vs just charging with straight propane?

Mark,

Years ago, an acquaintance accidentally did just that. As far as we could tell, it did no damage. It was real anemic as A/C goes, but I'm sure it
was better or worse than it worked when it was charged with R-12. I do no that both C3H8 and R-12 had very similar P/T curves at room and somewhat
higher temperatures.

Then there is the fact that my old halogen detector died. I do still have hope of recovering it, but I also have a mystery leak in my propane tank.
I stumbled across a combustible gas leak detector at an advantageous price. After I find where the propane tank is leaking, I am going to charge my
wife's car's A/C with propane and hope to find where that is leaking. So, I will let you know when I know more.

Matt
--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit
 
Matt, I am sure that you already know this, but, the shut off valve on the
propane tank needs to be either fully on and tight, or fully off and tight.
There is no mid point packing on the shaft. Another leak source is the
check ball on the filler fitting. It gets sticky from lack of use. The fix
is simple, a bit of spray lube sprayed into the tube followed by movement
of the spring loaded ball with a dowel until it is free. Hope this helps.
Jim Hupy

> >
> > Speaking of which, I've never used any sort of HC12 in an AC, but I do
> understand the benefits of doing so over charging with 134a or even R12...
> > However, what is the benefit of using a product like Duracool, vs just
> charging with straight propane?
>
> Mark,
>
> Years ago, an acquaintance accidentally did just that. As far as we could
> tell, it did no damage. It was real anemic as A/C goes, but I'm sure it
> was better or worse than it worked when it was charged with R-12. I do no
> that both C3H8 and R-12 had very similar P/T curves at room and somewhat
> higher temperatures.
>
> Then there is the fact that my old halogen detector died. I do still have
> hope of recovering it, but I also have a mystery leak in my propane tank.
> I stumbled across a combustible gas leak detector at an advantageous
> price. After I find where the propane tank is leaking, I am going to
> charge my
> wife's car's A/C with propane and hope to find where that is leaking. So,
> I will let you know when I know more.
>
> Matt
> --
> Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
> '73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
> Now with both true Keyless and remote entry
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
> ...However, what is the benefit of using a product like Duracool, vs just charging with straight propane?
The 35% butane in Duracool changes the P/T curve vs straight propane. Makes it more efficient in the design range of the R-12
compressor/condenser/evaporator system.

If you don't want to spend a lot, get some camp stove fuel and combine it with the propane. Mix 19.56 oz. of propane with the contents of one 16 oz
can of 80/20 campstove fuel to produce 35.56 ounces of HC refrigerant for an R-12 system.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"Highest price does not guarantee highest quality."
 
I use the plastic handle of the large screwdriver and tap around the filler
neck. That also helps to seat the ball.

> Matt, I am sure that you already know this, but, the shut off valve on the
> propane tank needs to be either fully on and tight, or fully off and tight.
> There is no mid point packing on the shaft. Another leak source is the
> check ball on the filler fitting. It gets sticky from lack of use. The fix
> is simple, a bit of spray lube sprayed into the tube followed by movement
> of the spring loaded ball with a dowel until it is free. Hope this helps.
> Jim Hupy
>

>

> > >
> > > Speaking of which, I've never used any sort of HC12 in an AC, but I do
> > understand the benefits of doing so over charging with 134a or even
> R12...
> > > However, what is the benefit of using a product like Duracool, vs just
> > charging with straight propane?
> >
> > Mark,
> >
> > Years ago, an acquaintance accidentally did just that. As far as we
> could
> > tell, it did no damage. It was real anemic as A/C goes, but I'm sure it
> > was better or worse than it worked when it was charged with R-12. I do
> no
> > that both C3H8 and R-12 had very similar P/T curves at room and somewhat
> > higher temperatures.
> >
> > Then there is the fact that my old halogen detector died. I do still
> have
> > hope of recovering it, but I also have a mystery leak in my propane tank.
> > I stumbled across a combustible gas leak detector at an advantageous
> > price. After I find where the propane tank is leaking, I am going to
> > charge my
> > wife's car's A/C with propane and hope to find where that is leaking.
> So,
> > I will let you know when I know more.
> >
> > Matt
> > --
> > Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
> > '73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control
> Arms
> > Now with both true Keyless and remote entry
> > SE Michigan - Twixt A2 and Detroit
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>

--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
My old SOB had a leak at the fitting for the fill valve. I had to dump the entire tank remove the valve and reseal. Of course it took me two attempts :(

________________________________
From: Gmclist on behalf of Matt Colie
Sent: Thursday, December 15, 2016 4:17:33 PM
To: gmclist
Subject: Re: [GMCnet] AC pressure switch R12/134a ?

>
> Speaking of which, I've never used any sort of HC12 in an AC, but I do understand the benefits of doing so over charging with 134a or even R12...
> However, what is the benefit of using a product like Duracool, vs just charging with straight propane?

Mark,

Years ago, an acquaintance accidentally did just that. As far as we could tell, it did no damage. It was real anemic as A/C goes, but I'm sure it
was better or worse than it worked when it was charged with R-12. I do no that both C3H8 and R-12 had very similar P/T curves at room and somewhat
higher temperatures.

Then there is the fact that my old halogen detector died. I do still have hope of recovering it, but I also have a mystery leak in my propane tank.
I stumbled across a combustible gas leak detector at an advantageous price. After I find where the propane tank is leaking, I am going to charge my
wife's car's A/C with propane and hope to find where that is leaking. So, I will let you know when I know more.

Matt
--
Matt & Mary Colie - Members GMCMI, GMCGL, GMCES
'73 Glacier 23 - Still Loving OE Rear Drum Brake with Applied Control Arms
Now with both true Keyless and remote entry
SE Michigan - Twixt A2 and Detroit

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